To me it's rappers trying to imitate hip hop/rap culture in USA, which often looks like cosplay and not sth authentic, but its not inherently bad thing to me.
Did you know that many Mongolian rappers use AAVE (african american english) for various reasons, some include just wanting to show that their rap is indeed hip hop music- aka using things that are iconic to music genre similar as BTS rappers do in those pictures, some are to express things they can't in their own language. I did essay on this for a course about global use of English ^^;
People borrow from cultures to show and portray different things, it's not unnecessarily mockery or sth bad to me.